[Exam Tutorial] CHMA11 2010 Midterm Questions

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School

University of Toronto Scarborough

Department

Chemistry

Course

CHMA11H3

Professor

all

Semester

Winter

Description

Multiple Choice Choose the one alternative that best completes the statement or answers
the question.
1) For BeCl , 2he dipole moment of the molecule, hybridization on the central atom, and
number of lone pairs on the central atom are:
a) None, sp , two
b) Toward Be, sp , none
c) Away from Be, sp , one
d) Toward Be, sp, one
e) None, sp, none
2) Choose the INCORRECT statement about PCI
5
3
a) P has sp d hybridization.
b) Each Cl has 3 lone pairs.
σ
c) There are 5 bonds
d) P has one lone pair
e) There are no π bonds.
3) How would replacing a benzene C and its H with a N atom (C H N) affec5 t5e delocalized
electrons?
a) The N can have delocalized electrons like C.
b) There would be no delocalized electrons but a double bond between the N and the C
on each side of the N
c) There would be no delocalized electrons but a double bond between the N and a C
d) The molecule would not be stable
e) Only the five C atoms would be included in the delocalized electrons.
5) Arrange the following compounds in order of increasing boiling point: I 1-propanol,
CH C3 Ch2OH;2II 1,2-propanediol, CH Ch(OH) 3H OH; III 1,223-propanetriol,
(glycerol), HOCH CH(OH)CH OH
2 2
a) I, III,II b) I,II,III c) III, I,II d) III,II, I E) II,III,I 8) The factor that has the largest effect on vapor pressure is:
a) Liquid mole weight
b) Liquid surface area
c) Volume available for vapor
d) Molecular dipole moment
e) Presence of H bonding
14) Solutions are made that contrain 0.1 moles of each of the following compounds below in 1-g
of H 2. Choose the compound whose solution will have the lowest freezing point.
a) KCLO 3 b) NaBr c) MgCl 2 d) CO 2 E) MgSO 4
16) Which of the following statements is correct?
a) A reaction rate cannot be calculated from the collision frequency alone.
b) A zero order reaction depends on the concentrations of reactants.
C) The number of collisions has no effect on the rate constant.
D) The orientation of a collision does not affect the rate constant.
E) a commonly stated rule of thumb is that reaction rates triple for a temperature increase of
about 10 C.
18) For a reaction with a second order rate constant, which is the correct unit?
-2
A) M X time
-2
b) M X time
c) M x time -1
D) M x time -1
E) 1
20) Which of the following lowers the activation energy of a reaction?
A) Lowering the temperature
B) Adding a catalyst
c) Adding a reactants
d) Raising the temperature
E) Removing products
21) Consider the reaction: ↔ Δ o
2SO (2) + O (2) 2SO 3g) H = -196.6 kJ/mol
The equilibrium is displaced to the left if:
a) The temperature is raised
b) Some sulfur dioxide is added
c) The pressure is raised
d) Some sulfur trioxide is removed
e) None of these
25) Write the equilibrium constant expression for the following reaction:
6CO 2(g) 6 H 2(l) ↔ C 6 12(s6 + 6O (g2
6
C 6 O12 ¿
¿
a) K c ¿
6
[CO ]2
¿
H
6[¿¿2O] 6
b) K = [CO ]2
c [O ]6
2
¿
[C 6 O12 6
c) K c 6 6
[H 2] [CO ] 2
O
6
[¿¿2]
d) K C 6
[CO 2
¿
6
[O2]
e) K c
[CO ]2
7) The relationship between the vapor pressure of a liquid and temperature can be
expressed by the Clausius-Clapeyron Equation: